<u># 用法</u>
<em>Date 对象用于处理日期和时间</em>
<u># 语法</u>
<em>const myDate</em> = <b>new Date</b> 				<em>// 当前日期和时间</em>
<em>const myDate</em> = <b>new Date( )</b> 			<em>// 当前日期和时间</em>
<em>const myDate</em> = <b>new Date</b>( <s>milliseconds</s> )	<em>// 毫秒或微秒</em>
<em>const myDate</em> = <b>new Date</b>( <s>dateString</s> )	<em>// 时间字符串，如：'2020/06/17 12:30:50'、2020-06-17</em>
<em>const myDate</em> = <b>new Date</b>( <s>year</s>, <s>month</s>, <s>day</s>, <s>hours</s>, <s>minutes</s>, <s>seconds</s>, <s>milliseconds</s>)	<em>// 年、月、日、时、分、秒、毫秒</em>
<u># 示例</u>
<em>const myDate</em> = <b>new Date</b>( <s>1592323996272</s> )
<em>const myDate</em> = <b>new Date</b>( <s>'2020-4-26'</s> )
<em>const myDate</em> = <b>new Date</b>( <s>'2020/4/26 12:30:50'</s> )
<em>const myDate</em> = <b>new Date</b>( <s>2020</s>, <s>6</s>, <s>17</s>, <s>0</s>, <s>15</s>, <s>20</s>, <s>30</s>)
<em>const myDate</em> = <b>new Date</b>( <s>'2020'</s>, <s>'6'</s>, <s>'17'</s>, <s>'0'</s>, <s>'15'</s>, <s>'20'</s>, <s>'30'</s>)